.11' 



PHYSIOLOGY "!' MCSCI.KS AND NKK\ I s. 



t h< i Mil i >f the nx|, mid thus driving" the frame \\ it h the 

 rods from // to J. iu a direct j.m oppusitt 1 to that, of the 

 arrow on the indicating jilate, a point is reached at 

 which the trigger ' which is seen on the standard A , 

 and which ;:cts upward, tits into a corresponding notch 

 in the rod at a, thus preventing the re-ext elision of the 

 spring. It therefore remains compressed till pressure 



A 



I I'.. -J>. Sl'lil.NO MvncKAril. AS I'SKD BY DC IJolS H I V M. >N i '. 



Oil the trigger frees the frame, which then traverses the 

 whole length of the wires at a speed depending on the 

 strength of the spring, A.V.. in the direct i.m from .-1 to />', 

 that indicated by th<' arrow. 



In order to dc>eril>e the muscle-pulsation on this 

 plate, side liy side uilh ,t t he;-e is a lever \\ith an 

 indicating pein-il, such as was u>ed iii the former ex- 

 periment , t indicate the height of miix-iilar elevation 



